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Justin Bieber's non-stop promotional tour for his new album "Purpose" is finally catching up to him.

The singer has pulled the plug on several high profile promotional opportunities this week, canceling an appearance on "The Late Show With Stephen Colbert," as well as a taped performance that was to air during the Thanksgiving Day Parade on CBS, according to TMZ.

The website said The Biebs is dealing with "personal issues" but it isn't related to drugs or alcohol. "He's been on a virtual roller coaster," the site said, "with his moods swinging like a pendulum, and it's just become too much."

There's no doubt that Justin has been pounding the pavement, criss-crossing the country to promote his latest project, one that has been received fairly well critically and insanely well by the public.

This week, the album helped Justin shatter the 51-year-old record for most songs simultaneously on Billboard's Hot 100, with 17 of the deluxe edition's 18 songs charting. The record was previously owned by some group named the Beatles. Purpose also had the biggest first-week sales of the year for any album.

His break from the promotional tour is just about the only hiccup in Justin's life these days. He even appears as though he's been patching things up with on-again, off-again, on-again, off-again, on-again, off-again girlfriend Selena Gomez.

Over the weekend, the duo was seen together at a Los Angeles-area restaurant, where Justin serenaded her on the piano to "My Girl."